Evaporative cooling systems using a combination of evaporative pads and
extractor fans require greenhouses to be hermetic. The greatest concentration of greenhouses
in the world is located in southeast Spain, but these tend not to be hermetic structures and
consequently can only rely on fogging systems as evaporative cooling techniques.
Evaporative cooling boxes provide an alternative to such systems. Using a low-speed wind
tunnel, the present work has compared the performance of this system with four pads
of differing geometry and thickness manufactured by two different companies. The
results obtained show that the plastic packing in the cooling unit produces a pressure drop
of 11.05 Pa at 2 m·s−1
, which is between 51.27% and 94.87% lower than that produced by
the cellulose pads. This pressure drop was not influenced by increases in the water flow.
The evaporative cooling boxes presented greater saturation efficiency at the same flow,
namely 82.63%, as opposed to an aver...
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Evaporative cooling systems using a combination of evaporative pads and
extractor fans require greenhouses to be hermetic. The greatest concentration of greenhouses
in the world is located in southeast Spain, but these tend not to be hermetic structures and
consequently can only rely on fogging systems as evaporative cooling techniques.
Evaporative cooling boxes provide an alternative to such systems. Using a low-speed wind
tunnel, the present work has compared the performance of this system with four pads
of differing geometry and thickness manufactured by two different companies. The
results obtained show that the plastic packing in the cooling unit produces a pressure drop
of 11.05 Pa at 2 m·s−1
, which is between 51.27% and 94.87% lower than that produced by
the cellulose pads. This pressure drop was not influenced by increases in the water flow.
The evaporative cooling boxes presented greater saturation efficiency at the same flow,
namely 82.63%, as opposed to an average figure of 65% for the cellulose pads; and also
had a lower specific consumption of water, at around 3.05 L·h−1
·m−2
·°C−1
. Consequently,
we conclude that evaporative cooling boxes are a good option for cooling non-hermetic
greenhouses such as those most frequently used in the Mediterranean basin.
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